Electrical appliance



,fs tantially on the line VI- VI of Fig. 4. x

Patented Feb. 2, 1943 ELECTRICAL APPLIANCE Kenneth L. Woodman, Mansfield, Ohio, assignor to Westinghouse Electric- & .Manufacturing Company, East Pittsbu of Pennsylvania rgh, Pa., a corporation Application January 29, 1941, Serial No. 376,425

7 Claims.

This invention relates, in general, to readily detachable electrical connections and, more particularly, to appliance plug connector elements. In appliance lug parts of the female type, it

is important to not only obtain good electrical.

contact with a male plug part when inserted therein, but it is also important to provide a construction which is extremely rugged in construction, and will have a long life without impairment of the holding ability of the plug part. This is especially important where these plugs are used with electric heating appliances and, therefore, may be subjected to wide variations in temperature.

Accordingly, one object of this 'inventiongis to provide a novel plug construction of the famale type having resilientholding means outside of the electric circuit through the plug.

Another object of this invention is to provide a novel plug construction of the type described wherein the parts thereof are especially susceptible to easy assembly so as to be locked in operative position upon securenient of the 'plug halves together.

Another object of this arrangement is to provide a novel arrangement in a plug of the type described for anchoring conductorsleadirlg into the plug against forces tending to move the conductors outwardly'ofthe' plug. I

A still further object of this invention is to provide a novel plug construction of the type described which may be"easily"a'ssembled, and which'at the same time willbe capable of efficient operation, and have a long life.

These and other objects of this'invention' will become more apparent upon consideration "of the following detailed description of a preferred "embodiment thereof when "taken in connection with the attached drawing, in which:

Figure 1 is a plan View of a' connector plug constructed in accordance with this invention and showing a portion of a conductor associated therewith;

' body with all contacts and other parts removed; 7

i 4 is asectional' view taken substan ally on the line IV-IV of Fig. 2;

Fig. 5 is ,a substantially central sectional view through an assembled plug body, for example, on the line V-V of Fig.3; and v Fig. 6 is a transverse sectional view taken sub- In Fig. 1 there is illustrated a plug generally indicated by the numeral 2 having a plural conductor cord 4 associated therewith, together with a reinforcing sleeve 6 secured to the plug 2 for distributing the bending of cord 6 adjacent plug 2. The plug 2 comprises a'pair of identical plug halves 8 secured together in face-to-face relation by a pair of screws or rivets 10 passing through aligned apertures in the-plug halves. vInasmuch as the plug halves Bare identical in form, only One will be described in detail.

Referring to Fig. 2 of the drawing, it can be seen that each plug half 8 is provided at one end with a single central, semi-circular groove l2, which when the plug halves are assembled will form a central opening for receiving cord 4, and one end of reinforcing sleeve 6. inwardly of groove I2 of each plug half there is provided an enlarged grooved portion [4 for receiving an anchoring flange or the like (not shown) integral with reinforcing sleeve 6. The sleeve 6 is preferably of resilient material, such, for example,,as rubber or the like, so that it may be compressed slightly'whe'n the plug halves are assembledjon one end thereof. Inwardly of the enlarged groove portion M in each plug half there is: provided a pair of spaced opposed shoulgrooves I2, [4 formed in the plug body and are separated by integral cylindrical projections 26 formed on each plug half and bent around these projections to be secured together on the opposite side thereof by a binding 28 which may be of wire or cord.. The binding 28 effectively prevents withdrawal of cord14 with respect to plug body 2. The conductors 22 and 24 inwardlyv of binding 28 are separated to extend in opposite directions along thetransverse groovepassage l8 and into grooves 20 in the branch passagewaysyto be secured to one end of contactstrips 30 in the branch passages, respectively.

example s c ib as's, or'the like, and-i provided at the inner end thereof with a flatterminal portion. 32 having an aperture 36" tose These branch passage- 4 cure one of the conductors 22, 24 therefor, for example, as by welding or riveting. The aperture 36 in terminal portion 32 of each contact strip is adapted to be positioned on a relatively raised portion of a plug half having a relatively shallow circular depression 34 in the upper surface thereof, underlying the aperture 36 in the contact strip. The terminal portion 32 of each contact strip is further provided with a transversely extending slot 38 for a purpose to be hereinafter described. The outer end of each contact strip 35 is offset from the terminal portion 32 and transversely curved or grooved, as shown in Fig. 6 at 40, to provide shoulder portions 42 at opposite sides thereof, and laterally extending flanges 44 at the outer side of each shoulder 42, The extreme outer end of each contact strip 30 is bent laterally outwardly as at 46 to be seated in a depression 48 formed in its associated plug body half.

The slot 38 formed in terminal portion- 32 of each contact strip is adapted to overlie a relatively deep depression 58 in its associated plug body half 8, to receive the laterally bent end 54 of a spring strip 52, as shown in Fig. 4. Spring strip 52 may be of any desired resilient material, and is preferably constructed of stainless steel. The main portion of spring strip 52 extends in overlying relation with respect to contact strip 30 and is provided adjacent the outer end thereof with side ears extending towards the contact strip 35 and positioned to rest on shoulders 42 of the contact strip inside of flanges 44, as shown more particularly in Fig. 6. The extreme outer end of spring strip 52 is flared outwardly as at 58 to be received in depression 48 of the upper plug body, as viewed in Fig. 4, and the material of the strip is then reversely bent back along the outwardly flared portion and bowed outwardly as at Bil, to engage the bottom of groove 20 in upper plug body half 8.

From the foregoing description of the structure of the parts of the plug body constituting this invention, the advantage of this construction from an assembling point of view may be readily appreciated. Thus, in assembling a plug constructed in accordance with this invention, it will first be noted that the plug body halves are of identical construction, and, accordingly, only one style of plug body half need be stocked. Obviously the contact strips 30 may be assembled to conductors 22 and 24, and the conductors separated and bound at 28 prior to their assembly with the plug body. The contact strips 30 may be then positioned in grooves 20 in one plug body half 8, as shown in Fig. 2, for example, and the conductors 22 and 24 positioned along grooves I8 and about pin 25 in the manner shown, whereupon spring strips 52 may then be merely placed over each contact strip 30 with the angularly directed end 5 3 of each spring strip inserted through slot 38 of each contact strip. The other plug body half may be then placed over this structure and secured in position by screws Ill, or by rivets if desired, and the assembly is then complete. From the foregoing, it is obvious that the entire assembly of the plug may be completed without any special tools after the conductors 22 and 24 have been secured to contact strips 38. Furthermore, this assembly consists mainly in placing parts in grooves provided therefor in one plug body in the proper sequence, and thereafter merely securing the two halves of the plug body v together.

adapted to receive between each contact strip 30 and spring strip 52, a contact prong which may be provided on an electrical appliance such, for example, as a toaster, roaster, or hot plate. It is obvious that such a prong may readily enter between each contact strip and its associated spring strip due to the flared outer end construction of these strips, and that entry of such a prong into the plug body will cause strip 52 to move away from contact strip 30 to flatten out the reversely bent bowed portion 60 of spring strip 52 and bend the strip as a whole to thereby stress the spring strip to maintain the contact prong into firm engagement with contact strip 30.

It should be noted that the spring strips 52 are not connected in the electric circuit through the plug so that they are not subject to deterioration caused by alternating heating and cooling upon passage of various currents therethrough. This is of particular advantage in providing a plug which will have a long life and yet be efiicient in operation. It should also be noted that all the parts are secured within the plug body and assembled therewith without the aid of any securing means other than cooperating recesses and projections provided on the plug body parts and the contact and spring strips. It should also be noted that cord 4, by virtue of binding 28 is prevented from moving outwardly with respect to the plug in the event a pull is exerted on the cord to detach the plug with respect to appliance prong contacts.

Having described preferred embodiments of the invention in accordance with the patent statutes, it should be understood that the invention is not to be limited to the particular embodiment disclosed herein, inasmuch as it will be obvious, particularly to persons skilled in the art, that many changes and modifications may be made therein without departing from the broad spirit and scope of the invention. Therefore, it is desired that the following claims be interpreted as broadly as possible, and that they be limited only by the prior art and by what is expressly set forth therein.

I claim as my invention:

1. In a device of the type described, means of insulating material defining a passageway open at opposite ends thereof, a conducting strip positioned at one side of said passageway adjacent one end thereof, conducting means adapted to be connected to said strip and extend out through the other end of said passageway, and

i an outwardly bowed, resilient strip in said one In use, the plug constituting this invention is end of said passageway and having at least one end thereof adapted to cooperate with a contact inserted in said one end of said passageway to maintain said contact in pressure engagement with said strip, and having the other end thereof extending through an aperture in said strip and into a cavity in the wall of said passageway.

2. In a plug, an insulating body structure including a pair of identical plug halves adapted to be secured together in face to face relation, each of said plug halves having in its confronting face a pair of spaced substantially parallel grooves therein for freely receiving a contact strip, each of said strips having an opening adapted to be alignedwith a depression in the bottom wall of each groove, a resilient strip for cooperation with each contact strip and having one end transversely disposed to extend through the opening and into said depression the groove receiving said contact strips, an intermediate portion of each resilient strip being spaced from its associated contact strip, and the other end thereof being in engagement with said contact strip, whereby when said plug halves are secured together said resilient strip is operable to urge and maintain contact prongs inserted in said groove into engagement with said contact strips.

3. In a plug, an insulating body structure including a pair of identical plug halves adapted to be secured together in face to face relation, each of said plug halves having in its confronting face a pair of spaced substantially parallel grooves therein for freely receiving a contact strip, each of said strips having an opening adapted to be aligned with a depression in the bottom wall of its associated groove, a resilient strip for cooperation with each contact strip and having one end transversely disposed to extend through said opening and into said depression, an intermediate portion of each resilient strip being spaced from its associated contact strip, and the other end thereof being in engagement with said contact strip, whereby when said plug halves are secured together said resilient strip is operable to urge and maintain contact prongs inserted in said grooves into engagement with said contact strips, said strips having relatively outwardly flared outer end portions for facilitating the entrance of contact prongs therebetween, and transverse grooves at the outer end of said spaced plug grooves for receiving said flared nds of said strips.

4. In a contact construction, an elongated strip of conducting material having means adjacent one end thereof for facilitating connection of a conductor thereto, the other end of said conducting strip being grooved for cooperation with a contact prong, an intermediate transversely extending opening in said conducting strip, a resilient strip having an angularly disposed end adapted to be received in said opening, the other end of said resilient strip adapted to engage the grooved portion of said conducting strip, and at least intermediate portions of said strips being spaced from each other.

5. In a contact construction, a flatstrip of conducting material having means adjacent one end thereof for facilitating connection of a conductor thereto, the other end of said conducting strip being grooved for cooperation with a contact prong, a resilient strip adapted to be in opposed relation to said contact strip, the outer end of said resilient strip having flanges to engage the grooved portion of said conducting strip at opposite sides of said groove, to maintain said strips spaced an amount suflicient to permit the entrance of a contact prong therebetween.

6. In a device of the type described, means of insulating material defining a passageway open at opposite ends thereof, a conducting strip positioned at one side of said passageway adjacent one end thereof, conducting means adapted to be connected to said strip and extend out through the other end of said passageway, and a resilient strip in said one end of said passageway having at least one end thereof adapted to cooperate with a contact inserted in said one end of said passageway to maintain said contact in pressure engagement with said strip, and having the other end thereof extending through an apertur in said strip to prevent relative movement of said strips.

'7. In a contact construction, a flat strip of conducting material having side flanges and means adjacent one end thereof for facilitating connection of a conductor thereto, the other end of said conducting strip being grooved for cooperation with a contact prong a resilient strip adapted to be in opposed relation to said contact strip, the outer end of said resilient strip having flanges to engage the grooved portion of said conducting strip at opposite sides of said groove and between said side flanges to prevent relative lateral movement of said strips and to maintain said strips spaced an amount suflicient to permit the entrance of a contact prong therebetween.

KENNETH L. WOO-DMAN. 

